Reutilizing Waste Iron Tailing Powders as Filler in Mortar to Realize Cement Reduction and Strength Enhancement

Abstract

Recently, the massive accumulation of waste iron tailings powder (WITP) has resulted in significant environmental pollution. To solve this problem, this paper proposes an original mortar replacement (M) method to reuse waste solids and reduce cement consumption. In the experiment, the author employed an M method which replaces water, cement, and sand with WITP under constant water/cement and found that the strength development can be significantly improved. Specifically, a mortar with 20% WITP replacement can obtain a 30.95% improvement in strength development. To study the internal mechanism, we performed experiments such as thermogravimetric analysis (TGA), mercury intrusion porosimetry (MIP), and SEM. The results demonstrate that the nucleation effect and pozzolanic effect of WITP can help promote cement hydration, and MIP reveals that WITP can effectively optimize pore structure. In addition, 1 kg 20% WITP mortar reduced cement consumption by 20%, which saves 19.98% of the economic cost. Comprehensively, our approach achieves the effective utilization of WITP and provides a favorable reference for practical engineering.

The Influence of Iron Tailings Powder on the Properties on the Performances of Cement Concrete with Machine-Made Sand

“…The compressive strength of cement concrete increased when the dosages of ITP increased from 0% to 7%, which was ascribed to the fact that the ITP showed a higher specific surface area than the cement. The ITP filled the pores between the particles of the cementitious material and optimized the particle grading of the cementitious material [27][28][29], which reduced the porosity of the concrete and made the concrete more dense. Therefore, the compressive strength was improved by adding the ITP.…”

Preparation of Mineral Admixture from Iron Tailings with Steel Slag-Desulfurization Ash and Its Application to Concrete

“…In recent years, the massive accumulation of solid waste, such as iron tailings and red mud, has caused serious problems to the ecological environment [ 1 , 2 , 3 ]. Studies related to iron tailings have described that the annual production of iron tailings in China is 47.5 million tons [ 4 ]. However, the annual comprehensive utilization rate of iron tailings is only 18.9%, and its utilization rate is far below the minimum standard of 20% in China [ 5 ].…”